You know how your mom used to yell that playing video games would turn your brain into mush? Turns out she was exactly wrong. A new study shows that playing Super Mario 64 for half an hour a day over the course of two months causes a "significant" increase in brain size.

What makes this study compelling is that causation bit. "While previous studies have shown differences in brain structure of video gamers, the present study can demonstrate the direct causal link between video gaming and a volumetric brain increase," says study leader Simon Kühn. "This proves that specific brain regions can be trained by means of video games." And that's a really good thing when it comes to stuff like helping soldiers recover from PTSD.

This is neat news, but don't go crazy with it. The study was relatively small—just 23 adults—so not everybody will get the same results. Plus, playing too many video games can actually make certain parts of your brain shrink. So actually, your mom was half right. [CNET]